1 /* Copyright (c) 2004-2005, 2007, 2009-2014. The SimGrid Team.
2 * All rights reserved. */
4 /* This program is free software; you can redistribute it and/or modify it
5 * under the terms of the license (GNU LGPL) which comes with this package. */
9 #include "internal_config.h"
15 #include <sys/syscall.h>
19 #include <linux/futex.h>
23 #include "xbt/parmap.h"
25 #include "xbt/function_types.h"
26 #include "xbt/dynar.h"
27 #include "xbt/xbt_os_thread.h"
28 #include "xbt/sysdep.h"
29 #include "simix/smx_private.h"
31 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(xbt_parmap, xbt, "parmap: parallel map");
36 } e_xbt_parmap_flag_t;
38 static void xbt_parmap_set_mode(xbt_parmap_t parmap, e_xbt_parmap_mode_t mode);
39 static void *xbt_parmap_worker_main(void *parmap);
40 static void xbt_parmap_work(xbt_parmap_t parmap);
42 static void xbt_parmap_posix_master_wait(xbt_parmap_t parmap);
43 static void xbt_parmap_posix_worker_signal(xbt_parmap_t parmap);
44 static void xbt_parmap_posix_master_signal(xbt_parmap_t parmap);
45 static void xbt_parmap_posix_worker_wait(xbt_parmap_t parmap, unsigned round);
48 static void xbt_parmap_futex_master_wait(xbt_parmap_t parmap);
49 static void xbt_parmap_futex_worker_signal(xbt_parmap_t parmap);
50 static void xbt_parmap_futex_master_signal(xbt_parmap_t parmap);
51 static void xbt_parmap_futex_worker_wait(xbt_parmap_t parmap, unsigned round);
52 static void futex_wait(unsigned *uaddr, unsigned val);
53 static void futex_wake(unsigned *uaddr, unsigned val);
56 static void xbt_parmap_busy_master_wait(xbt_parmap_t parmap);
57 static void xbt_parmap_busy_worker_signal(xbt_parmap_t parmap);
58 static void xbt_parmap_busy_master_signal(xbt_parmap_t parmap);
59 static void xbt_parmap_busy_worker_wait(xbt_parmap_t parmap, unsigned round);
62 static void xbt_parmap_mc_work(xbt_parmap_t parmap, int worker_id);
63 static void *xbt_parmap_mc_worker_main(void *arg);
67 * \brief Parallel map structure
69 typedef struct s_xbt_parmap {
70 e_xbt_parmap_flag_t status; /**< is the parmap active or being destroyed? */
71 unsigned work; /**< index of the current round */
72 unsigned thread_counter; /**< number of workers that have done the work */
74 unsigned int num_workers; /**< total number of worker threads including the controller */
75 xbt_os_thread_t *workers; /**< worker thread handlers */
76 void_f_pvoid_t fun; /**< function to run in parallel on each element of data */
77 xbt_dynar_t data; /**< parameters to pass to fun in parallel */
78 std::atomic<unsigned int> index; /**< index of the next element of data to pick */
83 int_f_pvoid_pvoid_t snapshot_compare;
89 xbt_os_cond_t ready_cond;
90 xbt_os_mutex_t ready_mutex;
91 xbt_os_cond_t done_cond;
92 xbt_os_mutex_t done_mutex;
94 /* fields that depend on the synchronization mode */
95 e_xbt_parmap_mode_t mode; /**< synchronization mode */
96 void (*master_wait_f)(xbt_parmap_t); /**< wait for the workers to have done the work */
97 void (*worker_signal_f)(xbt_parmap_t); /**< signal the master that a worker has done the work */
98 void (*master_signal_f)(xbt_parmap_t); /**< wakes the workers threads to process tasks */
99 void (*worker_wait_f)(xbt_parmap_t, unsigned); /**< waits for more work */
103 * \brief Thread data transmission structure
105 typedef struct s_xbt_parmap_thread_data{
108 } s_xbt_parmap_thread_data_t;
110 typedef s_xbt_parmap_thread_data_t *xbt_parmap_thread_data_t;
113 * \brief Creates a parallel map object
114 * \param num_workers number of worker threads to create
115 * \param mode how to synchronize the worker threads
116 * \return the parmap created
118 xbt_parmap_t xbt_parmap_new(unsigned int num_workers, e_xbt_parmap_mode_t mode)
122 XBT_DEBUG("Create new parmap (%u workers)", num_workers);
124 /* Initialize the thread pool data structure */
125 xbt_parmap_t parmap = xbt_new0(s_xbt_parmap_t, 1);
126 parmap->workers = xbt_new(xbt_os_thread_t, num_workers);
128 parmap->num_workers = num_workers;
129 parmap->status = XBT_PARMAP_WORK;
130 xbt_parmap_set_mode(parmap, mode);
132 /* Create the pool of worker threads */
133 xbt_parmap_thread_data_t data;
134 parmap->workers[0] = NULL;
136 unsigned int core_bind = 0;
138 for (i = 1; i < num_workers; i++) {
139 data = xbt_new0(s_xbt_parmap_thread_data_t, 1);
140 data->parmap = parmap;
142 parmap->workers[i] = xbt_os_thread_create(NULL, xbt_parmap_worker_main,
145 xbt_os_thread_bind(parmap->workers[i], core_bind);
146 if(core_bind!=xbt_os_get_numcores()){
158 * \brief Creates a parallel map object
159 * \param num_workers number of worker threads to create
160 * \param mode how to synchronize the worker threads
161 * \return the parmap created
163 xbt_parmap_t xbt_parmap_mc_new(unsigned int num_workers, e_xbt_parmap_mode_t mode)
167 XBT_DEBUG("Create new parmap (%u workers)", num_workers);
169 /* Initialize the thread pool data structure */
170 xbt_parmap_t parmap = xbt_new0(s_xbt_parmap_t, 1);
171 parmap->workers = xbt_new(xbt_os_thread_t, num_workers);
173 parmap->num_workers = num_workers;
174 parmap->status = XBT_PARMAP_WORK;
175 xbt_parmap_set_mode(parmap, mode);
177 /* Create the pool of worker threads */
178 xbt_parmap_thread_data_t data;
179 parmap->workers[0] = NULL;
180 for (i = 1; i < num_workers; i++) {
181 data = xbt_new0(s_xbt_parmap_thread_data_t, 1);
182 data->parmap = parmap;
184 parmap->workers[i] = xbt_os_thread_create(NULL, xbt_parmap_mc_worker_main,
192 * \brief Destroys a parmap
193 * \param parmap the parmap to destroy
195 void xbt_parmap_destroy(xbt_parmap_t parmap)
201 parmap->status = XBT_PARMAP_DESTROY;
202 parmap->master_signal_f(parmap);
205 for (i = 1; i < parmap->num_workers; i++)
206 xbt_os_thread_join(parmap->workers[i], NULL);
208 xbt_os_cond_destroy(parmap->ready_cond);
209 xbt_os_mutex_destroy(parmap->ready_mutex);
210 xbt_os_cond_destroy(parmap->done_cond);
211 xbt_os_mutex_destroy(parmap->done_mutex);
213 xbt_free(parmap->workers);
218 * \brief Sets the synchronization mode of a parmap.
219 * \param parmap a parallel map object
220 * \param mode the synchronization mode
222 static void xbt_parmap_set_mode(xbt_parmap_t parmap, e_xbt_parmap_mode_t mode)
224 if (mode == XBT_PARMAP_DEFAULT) {
226 mode = XBT_PARMAP_FUTEX;
228 mode = XBT_PARMAP_POSIX;
235 case XBT_PARMAP_POSIX:
236 parmap->master_wait_f = xbt_parmap_posix_master_wait;
237 parmap->worker_signal_f = xbt_parmap_posix_worker_signal;
238 parmap->master_signal_f = xbt_parmap_posix_master_signal;
239 parmap->worker_wait_f = xbt_parmap_posix_worker_wait;
241 parmap->ready_cond = xbt_os_cond_init();
242 parmap->ready_mutex = xbt_os_mutex_init();
243 parmap->done_cond = xbt_os_cond_init();
244 parmap->done_mutex = xbt_os_mutex_init();
248 case XBT_PARMAP_FUTEX:
250 parmap->master_wait_f = xbt_parmap_futex_master_wait;
251 parmap->worker_signal_f = xbt_parmap_futex_worker_signal;
252 parmap->master_signal_f = xbt_parmap_futex_master_signal;
253 parmap->worker_wait_f = xbt_parmap_futex_worker_wait;
255 xbt_os_cond_destroy(parmap->ready_cond);
256 xbt_os_mutex_destroy(parmap->ready_mutex);
257 xbt_os_cond_destroy(parmap->done_cond);
258 xbt_os_mutex_destroy(parmap->done_mutex);
261 xbt_die("Futex is not available on this OS.");
264 case XBT_PARMAP_BUSY_WAIT:
265 parmap->master_wait_f = xbt_parmap_busy_master_wait;
266 parmap->worker_signal_f = xbt_parmap_busy_worker_signal;
267 parmap->master_signal_f = xbt_parmap_busy_master_signal;
268 parmap->worker_wait_f = xbt_parmap_busy_worker_wait;
270 xbt_os_cond_destroy(parmap->ready_cond);
271 xbt_os_mutex_destroy(parmap->ready_mutex);
272 xbt_os_cond_destroy(parmap->done_cond);
273 xbt_os_mutex_destroy(parmap->done_mutex);
276 case XBT_PARMAP_DEFAULT:
283 * \brief Applies a list of tasks in parallel.
284 * \param parmap a parallel map object
285 * \param fun the function to call in parallel
286 * \param data each element of this dynar will be passed as an argument to fun
288 void xbt_parmap_apply(xbt_parmap_t parmap, void_f_pvoid_t fun, xbt_dynar_t data)
290 /* Assign resources to worker threads (we are maestro here)*/
294 parmap->master_signal_f(parmap); // maestro runs futex_wait to wake all the minions (the working threads)
295 xbt_parmap_work(parmap); // maestro works with its minions
296 parmap->master_wait_f(parmap); // When there is no more work to do, then maestro waits for the last minion to stop
297 XBT_DEBUG("Job done"); // ... and proceeds
301 * \brief Returns a next task to process.
303 * Worker threads call this function to get more work.
305 * \return the next task to process, or NULL if there is no more work
307 void* xbt_parmap_next(xbt_parmap_t parmap)
309 unsigned int index = parmap->index++;
310 if (index < xbt_dynar_length(parmap->data)) {
311 return xbt_dynar_get_as(parmap->data, index, void*);
316 static void xbt_parmap_work(xbt_parmap_t parmap)
319 while ((index = parmap->index++)
320 < xbt_dynar_length(parmap->data))
321 parmap->fun(xbt_dynar_get_as(parmap->data, index, void*));
325 * \brief Main function of a worker thread.
326 * \param arg the parmap
328 static void *xbt_parmap_worker_main(void *arg)
330 xbt_parmap_thread_data_t data = (xbt_parmap_thread_data_t) arg;
331 xbt_parmap_t parmap = data->parmap;
333 smx_context_t context = SIMIX_context_new(NULL, 0, NULL, NULL, NULL);
334 SIMIX_context_set_current(context);
336 XBT_DEBUG("New worker thread created");
338 /* Worker's main loop */
340 parmap->worker_wait_f(parmap, ++round);
341 if (parmap->status == XBT_PARMAP_WORK) {
343 XBT_DEBUG("Worker %d got a job", data->worker_id);
345 xbt_parmap_work(parmap);
346 parmap->worker_signal_f(parmap);
348 XBT_DEBUG("Worker %d has finished", data->worker_id);
350 /* We are destroying the parmap */
352 SIMIX_context_free(context);
362 * \brief Applies a list of tasks in parallel.
363 * \param parmap a parallel map object
364 * \param fun the function to call in parallel
365 * \param data each element of this dynar will be passed as an argument to fun
367 int xbt_parmap_mc_apply(xbt_parmap_t parmap, int_f_pvoid_pvoid_t fun,
368 void* data, unsigned int length, void* ref_snapshot)
370 /* Assign resources to worker threads */
371 parmap->snapshot_compare = fun;
372 parmap->mc_data = data;
375 parmap->length = length;
376 parmap->ref_snapshot = ref_snapshot;
377 parmap->master_signal_f(parmap);
378 xbt_parmap_mc_work(parmap, 0);
379 parmap->master_wait_f(parmap);
380 XBT_DEBUG("Job done");
381 return parmap->finish;
384 static void xbt_parmap_mc_work(xbt_parmap_t parmap, int worker_id)
386 unsigned int data_size = (parmap->length / parmap->num_workers) +
387 ((parmap->length % parmap->num_workers) ? 1 :0);
388 void* start = (char*)parmap->mc_data + (data_size*worker_id*sizeof(void*));
389 void* end = MIN((char *)start + data_size* sizeof(void*), (char*)parmap->mc_data + parmap->length*sizeof(void*));
391 //XBT_CRITICAL("Worker %d : %p -> %p (%d)", worker_id, start, end, data_size);
393 while ( start < end && parmap->finish == -1) {
394 //XBT_CRITICAL("Starting with %p", start);
395 int res = parmap->snapshot_compare(*(void**)start, parmap->ref_snapshot);
396 start = (char *)start + sizeof(start);
399 parmap->finish = ((char*)start - (char*)parmap->mc_data) / sizeof(void*);
400 //XBT_CRITICAL("Find good one %p (%p)", start, parmap->mc_data);
407 * \brief Main function of a worker thread.
408 * \param arg the parmap
410 static void *xbt_parmap_mc_worker_main(void *arg)
412 xbt_parmap_thread_data_t data = (xbt_parmap_thread_data_t) arg;
413 xbt_parmap_t parmap = data->parmap;
415 /* smx_context_t context = SIMIX_context_new(NULL, 0, NULL, NULL, NULL); */
416 /* SIMIX_context_set_current(context); */
418 XBT_DEBUG("New worker thread created");
420 /* Worker's main loop */
422 parmap->worker_wait_f(parmap, ++round);
423 if (parmap->status == XBT_PARMAP_WORK) {
425 XBT_DEBUG("Worker %d got a job", data->worker_id);
427 xbt_parmap_mc_work(parmap, data->worker_id);
428 parmap->worker_signal_f(parmap);
430 XBT_DEBUG("Worker %d has finished", data->worker_id);
432 /* We are destroying the parmap */
442 static void futex_wait(unsigned *uaddr, unsigned val)
444 XBT_VERB("Waiting on futex %p", uaddr);
445 syscall(SYS_futex, uaddr, FUTEX_WAIT_PRIVATE, val, NULL, NULL, 0);
448 static void futex_wake(unsigned *uaddr, unsigned val)
450 XBT_VERB("Waking futex %p", uaddr);
451 syscall(SYS_futex, uaddr, FUTEX_WAKE_PRIVATE, val, NULL, NULL, 0);
456 * \brief Starts the parmap: waits for all workers to be ready and returns.
458 * This function is called by the controller thread.
460 * \param parmap a parmap
462 static void xbt_parmap_posix_master_wait(xbt_parmap_t parmap)
464 xbt_os_mutex_acquire(parmap->done_mutex);
465 if (parmap->thread_counter < parmap->num_workers) {
466 /* wait for all workers to be ready */
467 xbt_os_cond_wait(parmap->done_cond, parmap->done_mutex);
469 xbt_os_mutex_release(parmap->done_mutex);
473 * \brief Ends the parmap: wakes the controller thread when all workers terminate.
475 * This function is called by all worker threads when they end (not including
478 * \param parmap a parmap
480 static void xbt_parmap_posix_worker_signal(xbt_parmap_t parmap)
482 xbt_os_mutex_acquire(parmap->done_mutex);
483 if (++parmap->thread_counter == parmap->num_workers) {
484 /* all workers have finished, wake the controller */
485 xbt_os_cond_signal(parmap->done_cond);
487 xbt_os_mutex_release(parmap->done_mutex);
491 * \brief Wakes all workers and waits for them to finish the tasks.
493 * This function is called by the controller thread.
495 * \param parmap a parmap
497 static void xbt_parmap_posix_master_signal(xbt_parmap_t parmap)
499 xbt_os_mutex_acquire(parmap->ready_mutex);
500 parmap->thread_counter = 1;
502 /* wake all workers */
503 xbt_os_cond_broadcast(parmap->ready_cond);
504 xbt_os_mutex_release(parmap->ready_mutex);
508 * \brief Waits for some work to process.
510 * This function is called by each worker thread (not including the controller)
511 * when it has no more work to do.
513 * \param parmap a parmap
514 * \param round the expected round number
516 static void xbt_parmap_posix_worker_wait(xbt_parmap_t parmap, unsigned round)
518 xbt_os_mutex_acquire(parmap->ready_mutex);
519 /* wait for more work */
520 if (parmap->work != round) {
521 xbt_os_cond_wait(parmap->ready_cond, parmap->ready_mutex);
523 xbt_os_mutex_release(parmap->ready_mutex);
528 * \brief Starts the parmap: waits for all workers to be ready and returns.
530 * This function is called by the controller thread.
532 * \param parmap a parmap
534 static void xbt_parmap_futex_master_wait(xbt_parmap_t parmap)
536 unsigned count = parmap->thread_counter;
537 while (count < parmap->num_workers) {
538 /* wait for all workers to be ready */
539 futex_wait(&parmap->thread_counter, count);
540 count = parmap->thread_counter;
545 * \brief Ends the parmap: wakes the controller thread when all workers terminate.
547 * This function is called by all worker threads when they end (not including
550 * \param parmap a parmap
552 static void xbt_parmap_futex_worker_signal(xbt_parmap_t parmap)
554 unsigned count = __sync_add_and_fetch(&parmap->thread_counter, 1);
555 if (count == parmap->num_workers) {
556 /* all workers have finished, wake the controller */
557 futex_wake(&parmap->thread_counter, INT_MAX);
562 * \brief Wakes all workers and waits for them to finish the tasks.
564 * This function is called by the controller thread.
566 * \param parmap a parmap
568 static void xbt_parmap_futex_master_signal(xbt_parmap_t parmap)
570 parmap->thread_counter = 1;
571 __sync_add_and_fetch(&parmap->work, 1);
572 /* wake all workers */
573 futex_wake(&parmap->work, INT_MAX);
577 * \brief Waits for some work to process.
579 * This function is called by each worker thread (not including the controller)
580 * when it has no more work to do.
582 * \param parmap a parmap
583 * \param round the expected round number
585 static void xbt_parmap_futex_worker_wait(xbt_parmap_t parmap, unsigned round)
587 unsigned work = parmap->work;
588 /* wait for more work */
589 while (work != round) {
590 futex_wait(&parmap->work, work);
597 * \brief Starts the parmap: waits for all workers to be ready and returns.
599 * This function is called by the controller thread.
601 * \param parmap a parmap
603 static void xbt_parmap_busy_master_wait(xbt_parmap_t parmap)
605 while (parmap->thread_counter < parmap->num_workers) {
606 xbt_os_thread_yield();
611 * \brief Ends the parmap: wakes the controller thread when all workers terminate.
613 * This function is called by all worker threads when they end.
615 * \param parmap a parmap
617 static void xbt_parmap_busy_worker_signal(xbt_parmap_t parmap)
619 __sync_add_and_fetch(&parmap->thread_counter, 1);
623 * \brief Wakes all workers and waits for them to finish the tasks.
625 * This function is called by the controller thread.
627 * \param parmap a parmap
629 static void xbt_parmap_busy_master_signal(xbt_parmap_t parmap)
631 parmap->thread_counter = 1;
632 __sync_add_and_fetch(&parmap->work, 1);
636 * \brief Waits for some work to process.
638 * This function is called by each worker thread (not including the controller)
639 * when it has no more work to do.
641 * \param parmap a parmap
642 * \param round the expected round number
644 static void xbt_parmap_busy_worker_wait(xbt_parmap_t parmap, unsigned round)
646 /* wait for more work */
647 while (parmap->work != round) {
648 xbt_os_thread_yield();